xref: /freebsd/sys/geom/label/g_label_ufs.c (revision f0adf7f5cdd241db2f2c817683191a6ef64a4e95)
1 /*-
2  * Copyright (c) 2002, 2003 Gordon Tetlow
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  *
14  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24  * SUCH DAMAGE.
25  */
26 
27 #include <sys/cdefs.h>
28 __FBSDID("$FreeBSD$");
29 
30 #include <sys/param.h>
31 #include <sys/systm.h>
32 #include <sys/kernel.h>
33 #include <sys/malloc.h>
34 
35 #include <ufs/ufs/dinode.h>
36 #include <ufs/ffs/fs.h>
37 
38 #include <geom/geom.h>
39 #include <geom/label/g_label.h>
40 
41 #define G_LABEL_UFS_DIR	"ufs"
42 
43 static const int superblocks[] = SBLOCKSEARCH;
44 
45 static void
46 g_label_ufs_taste(struct g_consumer *cp, char *label, size_t size)
47 {
48 	struct g_provider *pp;
49 	int error, sb, superblock;
50 	struct fs *fs;
51 
52 	g_topology_assert_not();
53 	pp = cp->provider;
54 	label[0] = '\0';
55 	/*
56 	 * Walk through the standard places that superblocks hide and look
57 	 * for UFS magic. If we find magic, then check that the size in the
58 	 * superblock corresponds to the size of the underlying provider.
59 	 * Finally, look for a volume label and create an appropriate
60 	 * provider based on that.
61 	 */
62 	for (sb = 0; (superblock = superblocks[sb]) != -1; sb++) {
63 		fs = (struct fs *)g_read_data(cp, superblock, SBLOCKSIZE,
64 		    &error);
65 		if (fs == NULL || error != 0)
66 			continue;
67 		/* Check for magic and make sure things are the right size */
68 		if (fs->fs_magic == FS_UFS1_MAGIC) {
69 			G_LABEL_DEBUG(1, "UFS1 file system detected on %s.",
70 			    pp->name);
71 			if (fs->fs_old_size * fs->fs_fsize !=
72 			    (int32_t)pp->mediasize) {
73 				g_free(fs);
74 				continue;
75 			}
76 		} else if (fs->fs_magic == FS_UFS2_MAGIC) {
77 			G_LABEL_DEBUG(1, "UFS2 file system detected on %s.",
78 			    pp->name);
79 			if (fs->fs_size * fs->fs_fsize !=
80 			    (int64_t)pp->mediasize) {
81 				g_free(fs);
82 				continue;
83 			}
84 		} else {
85 			g_free(fs);
86 			continue;
87 		}
88 		/* Check for volume label */
89 		if (fs->fs_volname[0] == '\0') {
90 			g_free(fs);
91 			continue;
92 		}
93 		strlcpy(label, fs->fs_volname, size);
94 		g_free(fs);
95 		break;
96 	}
97 }
98 
99 const struct g_label_desc g_label_ufs = {
100 	.ld_taste = g_label_ufs_taste,
101 	.ld_dir = G_LABEL_UFS_DIR
102 };
103